Small Interfering RNA (siRNA) and Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR): Emerging Molecular Tools for Genetic Manipulation

@#Gene manipulation tools have transformed biomedical research and improved the possibilities of their uses for therapeutic purposes. These tools have aided effective genomic modification in many organisms and have been successfully applied in biomedical engineering, biotechnology and biomedicine. They also shown a potential for therapeutic applications to alleviate genetic and non-genetic diseases. Small interfering RNA (siRNA) and clustered regularly inter-spaced short-palindromic repeat/associated-protein system (CRISPR/Cas) are two of the tools applied in genetic manipulation. This review aims to evaluate the molecular influence of siRNA and CRISPR/Cas as novel tools for genetic manipulations. This review discusses the molecular mechanism of siRNA and CRISPR/Cas, and the advantages and disadvantages of siRNA and CRISPR/Cas. This review also presents comparison between siRNA and CRISPR/Cas as potential tools for gene therapy. siRNA therapeutic applications occur through protein knockout without causing damage to cells. siRNA knocks down gene expression at the mRNA level, whereas CRISPR/Cas knocks out gene permanently at the DNA level. Inconclusion, gene manipulation tools have potential for applications that improve therapeutic strategies and plant-derived products, but ethical standards must be established before the clinical application of gene editing.

Dose-and Time-Dependent Suppression of Rac1 and STIM1 in Acute Myeloid Leukaemia Cell Line Model

@#Introduction: Rac1 and STIM1 genes are emerging therapeutic targets for cancers. However, their roles in acute myeloid leukaemia (AML) are not well understood. The goal of this study was to evaluate the effects of dose and time on Rac1 and STIM1 knockdown in the AML cell line model (THP-1 cells). Methods: THP-1 cells were transfected with siRac1 at doses of 50, 100, and 200 nM or dsiSTIM1 at doses of 2, 5, and 10 nM. Expression level of Rac1 and STIM1 then were assessed at time points between 12 and 72 h post-transfection using real-time reverse transcription polymerase chain reaction. Results: Compared to the control, 87% Rac1 knockdown was attained with 50 nM siRac1 at 24 h post-transfection, and 70% STIM1 knockdown was achieved with 10 nM dsiSTIM1 at 48 h post-transfection. Conclusion: These results show that effective knockdown of Rac1 and STIM1 is possible, and therapy that includes Rac1 and STIM1 inhibitors eventually could provide a new and highly effective strategy for AML treatment.

Antibacterial Efficacy and Drug-release Behavior Study of β-tricalcium Phosphate Micro-granules Against Staphylococcus aureus and Escherichia coli

@#Introduction: This study aims to investigate different residue sizes of β-tricalcium phosphate (β-TCP) micro-granules as carriers to assess antibacterial activity and drug-control release behavior of ampicillin (AMP-) and antimycotic (AMC-). Incorporation of antibiotic into the β-TCP micro-granules and it sustain release behavior could be used as alternative solution to reduce the risk of osteomyelitis and bone infections risks. Methods: Three different residue sizes (less than 300 µm, 300 µm and 600 µm) were prepared and coated with antibiotics solution (20 µg/µl of ampicillin and 100X antimycotic solution) by using two methods; dip and stream coating. After 72 h, 1.5 mL of distilled water was added to the treated (β-TCP) micro-granules at two different pH value (5.0 and 7.4). The extracted solution was further analyzed by Kirby Bauer disc diffusion test and spectrophotometer assay. Results: The solution containing AMC-(β-TCP) micro-granules with the size of 300 µm residue produced the largest inhibition zones against Escherichia coli (E. coli). All residue sizes coated with AMP- showed no antibacterial activity against both strains; Staphylococcus aureus (S. aureus) and E.coli. Additionally, the release behavior of AMC-(β-TCP) micro-granules was found not depending on the pH, but on the size of residue. Complete drug release was rapidly observed within 48 h. Conclusion: Based on this findings, it showed AMC-(β-TCP) micro-granules had an antibacterial activity against Gram-negative strain. Specifically, it can reduced the growth rate of E. coli and the rapid release behavior of AMC(β-TCP) micro-granules help in minimizing the risk-infections in early stage of implantation.

A Case Study of Distinctive Phenotypes Arising From Emanuel Syndrome in Two Karyotypically Identical Patients

@#Emanuel syndrome, also referred to as supernumerary der(22) or t(11;22) syndrome, is a rare genomic syndrome. Patients are normally presented with multiple congenital anomalies and severe developmental disabilities. Affected newborns usually carry a derivative chromosome 22 inherited from either parent, which stems from a balanced translocation between chromosomes 11 and 22. Unfortunately, identification of Emanuel syndrome carriers is difficult as balanced translocations do not typically present symptoms. We identified two patients diagnosed as Emanuel syndrome with identical chromosomal aberration: 47,XX,+der(22)t(11;22)(q24;q12.1)mat karyotype but presenting variable phenotypic features. Emanuel syndrome patients present variable phenotypes and karyotypes have also been inconsistent albeit the existence of a derivative chromosome 22. Our data suggests that there may exist accompanying genetic aberrations which influence the outcome of Emanuel syndrome phenotypes but it should be cautioned that more patient observations, diagnostic data and research is required before conclusions can be drawn on definitive karyotypic-phenotypic correlations.

Molecular Pathways for Nasopharyngeal Carcinoma focused on Acetaldehyde, Nitrosamines and Nicotine Exposures

@#Recently, one of the head and neck tumours located at the nasopharynx epithelium known as nasopharyngeal carcinoma (NPC) have been associated with few cancer-promoting compounds that derived from alcohol, salt preserved foods consumptions and tobacco smoking such as acetaldehyde, nitrosamine, nicotine. These cancer-promoting compounds present the ability to damage the genome and disrupt cellular metabolic processes. This review will discuss further on the molecular mechanism of acetaldehyde, nitrosamine, nicotine and NPC risk. Acetaldehyde can exert influence as carcinogen macromolecular adducts to cellular proteins and DNAs whilst nitrosamines that commonly found in preserved salted foods/diets can contribute as a powerful carcinogen via endogenous nitrosation and reactives molecules by CYP2E1. Nicotine present in tobacco could reacts with nitrosamine to form NNN and NNK known as carcinogenic agent. NNK mediates unstable reactive oxygen species that can induce DNA lesion (α -hydroxylation of NNN at positions 2’and 5’) and microenvironment alteration for tumorigenesis. In conclusion, this study suggests acetaldehydes, nitrosamine and nicotine may contribute to NPC tumourigenesis.

Nasopharyngeal Cancer : Geographic Variation and Risk Factors

@#Introduction: Nasopharyngeal cancer is known to be a rare malignancy that effects the head and neck region involving the nasopharynx. It has a 0.8% occurrence rate among all types of cancer and has many risk factors ranging from viral infections to dietary intake habits. This study aims in determining the geographical variations across the world and its associated risk factors with nasopharyngeal cancer. Methods: The study was initiated by extracting relevant literature articles from electronic databases such as PubMed, Science Direct and SEER from 2008-2018. Search strategy also included key terms; nasopharyngeal cancer, nasopharyngeal carcinoma, prevalence, risk factors, geographic variation, distribution, incidences, epidemiology and mortality. Results: Nasopharyngeal cancer is most common in Asia and China had the most number of new cases diagnosed in 2018. The standard incidence rate of nasopharyngeal cancer globally in 2018 was 1.5 per 100,000. The standardized mortality rate for nasopharyngeal cancer globally in 2018 was 0.84 per 100,000. The 5 identified countries with the highest mortality rates were China, Indonesia, Vietnam, India and Philippines accordingly. Among the risk factors attributing to the incidences of nasopharyngeal cancer are Epstein Barr Virus (EBV) infection, salted and preserved food consumption and tobacco smoking. Conclusion: Nasopharyngeal cancer is strongly associated with the variation of geographical regions therefore adequate knowledge, early detection, immediate administration of treatment and rapid detection is vital in reducing the global incidence burden.

Potential of Calcium Carbonate Nanoparticles for Therapeutic Applications

@#The application of nanoparticles (NPs) has attracted considerable attention as targeted delivery systems. CaCO3 has become the focus due to its advantages including affordability, low toxicity, biocompatibility, cytocompatibility, pH sensitivity and sedate biodegradability and environment friendly materials. In this article, we will discuss the potential roles of CaCO3-NPs in three major therapeutic applications; as antimicrobial, for drug delivery, and as gene delivery nanocarrier.